1. Field of the Invention
The invention relates to a control device adapted for use in a power supplying apparatus, more particularly to a multi-processor control device including at least two separate processors that are assigned to perform different sets of control functions. When one of the processors malfunctions, the other processors continue to work to resume operation of the power supplying apparatus. At the same time, the other processors activate an alarm generator to warn a system manager of the occurrence of a malfunction.
2. Description of the Related Art
Presently, the power supplying apparatus installed in a large target system (such as a network server) is usually connected to a main board of the target system by a power cable, thereby enabling the power supplying apparatus to provide operating power to the target system. The conventional power supplying apparatus installed in the large target system generally includes a plurality of power supplying units that are connected in parallel. Each power supplying unit includes a power converting circuit for converting an alternating current (AC) input into a direct current (DC) output that is provided to the target system and to a heat dissipating fan of the power supplying unit. The internal circuitry of the power supplying units is known to those skilled in the art and will not be described further. The power supplying apparatus further includes a control circuit board connected to the power supplying units. A detecting and alarm generating circuit on the control circuit board detects whether or not the power supplying units are functioning properly, and generates an alarm output upon detecting that any one of the power supplying units is malfunctioning. A protecting circuit detects whether or not the output voltages of the power supplying units are in a predetermined normal range, and disables the power supplying unit with the output voltage that is excessively high or excessively low. A load balancing circuit is employed to balance the power load of the power supplying units. Some conventional power supplying apparatus employ analog circuits to perform the aforesaid functions of detecting and alarm generating, over-voltage and under-voltage protection, and load balancing control. Other conventional power supplying apparatus employ digital means, such as a single microprocessor, to perform the same functions.
It is noted that the advantage of a simple circuit construction arises when a single microprocessor is used to perform the aforesaid functions instead of a number of analog circuits. However, when the single microprocessor is unable to work properly, all of the functions, such as detecting and alarm generating, over-voltage and under-voltage protection, and load balancing control, that are associated with the single microprocessor will be suspended. Such a condition will have an adverse effect on the target system, and can lead to data loss.
Therefore, the main object of the present invention is to provide a multi-processor control device including at least two separate processors that are assigned to perform different sets of control functions. When one of the processors malfunctions, the other processors continue to work to resume operation of a power supplying apparatus that incorporates the control device. At the same time, the other processors activate an alarm generator to warn a system manager of the occurrence of a malfunction so that the appropriate action can be done.
According to the present invention, a multi-processor control device is adapted for use in a power supplying apparatus that includes a plurality of power supplying units, and comprises:
at least two separate processors adapted to be connected to the power supplying units, the processors being adapted to jointly perform control functions associated with status monitoring and load balancing control of the power supplying units, the processors being connected to each other and further performing a continuous verification operation, in which signal exchange between the processors is continuously executed to enable each of the processors to verify whether or not other ones of the processors are operating normally, each of the processors being capable of generating a warning signal in the event that any one of the processors fails to respond thereto due to malfunctioning of the latter; and
an alarm generator connected to the processors and activated by the warning signal from any of the processors so as to generate a warning output.
In the preferred embodiment, an analog-to-digital converting circuit is connected to the processors and is adapted to be connected to the power supplying units. The analog-to-digital converting circuit is adapted to convert analog voltage outputs of the power supplying units into corresponding digital signals that are provided to the processors.
The processors include a load balancing processor and a status monitoring processor. The load balancing processor is adapted to control the power supplying units so as to balance power load of the same in accordance with the digital signals received from the analog-to-digital converting circuit. The status monitoring processor is operable so as to perform at least one of detecting output voltages and operating temperatures of the power supplying units, detecting whether or not the power supplying units are functioning properly and generating an alarm output upon detecting that any one of the power supplying units is malfunctioning, and protecting the power supplying units by disabling one of the power supplying units having the output voltage that is not within a predetermined normal range.